web.xml 各个标签详解

对于web项目，web.xml可有，也可以没有。但是对于大型的web项目使用web.xml会很方便的。

1.web.xml是项目的入口

2.web.xml可以做的事：

指定欢迎页面
指定错误页面、
命名与定制url
定制初始化参数
设置过滤器
.设置监听器
设置session过期时间

1<?xml version="1.0" encoding="UTF-8"?>

声明xml的版本

2<web-app>

指明xml使用的是哪个模式文件（即xsd，就是描述xml的规范）

3<display-name>

设置站点的标题显示内容

4<session-config>

设置用户登录的session时间

5<welcome-file-list>

设置访问站点项目名显示的欢迎页面，第一个不存在就显示第二个。第一个存在第二个就会不起作用。

6<servlet>

指定访问的所有路径都经过TestServlet.do处理器。

7<context-param />

用来设定web站台的环境参数，参数也可以xml文件。即加载各种配置文件。

8 <listener>

设置监听器

9<filter>

设置过滤器。

10<error-page>

指定错误的页面，可以通过“异常类型”或“错误码”来指定错误处理页面。

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
   http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
   <display-name>CLNContract</display-name>
   
   <session-config>
       <session-timeout>30</session-timeout>
   </session-config>

<welcome-file-list>

<welcome-file>index.jsp</welcome-file>

<welcome-file>index1.jsp</welcome-file>

</welcome-file-list>

<error-page>

<exception-type>java.lang.Exception<exception-type>

<location>/exception.jsp<location>

</error-page>

<error-page>

<exception-type>java.lang.NullException</exception-type>

<location>/error.jsp</location>

</error-page>

<error-page>

<error-code>404</error-code>

<location>/error404.jsp</location>

</error-page>

<servlet-name>servlet1</servlet-name>

<servlet-class>com.TestServlet</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>servlet1</servlet-name>

<url-pattern>*.do</url-pattern>

</servlet-mapping>

<context-param>
       <param-name>contextConfigLocation</param-name>
       <param-value>
classpath*:applicationContext*.xml
   </param-value>
   </context-param>
<filter>
<filter-name>systemFilter</filter-name>
<filter-class>com.chinalife.util.UrlFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>systemFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
       <filter-name>encodingFilter</filter-name>
       <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
       <init-param>
           <param-name>encoding</param-name>
           <param-value>UTF-8</param-value>
       </init-param>
       <init-param>
           <param-name>forceEncoding</param-name>
           <param-value>true</param-value>
       </init-param>
   </filter>
   <filter-mapping>
       <filter-name>encodingFilter</filter-name>
       <url-pattern>/*</url-pattern>
   </filter-mapping>
   <filter>
<filter-name>struts-cleanup</filter-name>
<filter-class>
org.apache.struts2.dispatcher.ActionContextCleanUp
</filter-class>
</filter>

   
   
   <filter>
       <filter-name>struts2</filter-name>
       <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
   </filter>
   <filter-mapping>
       <filter-name>struts2</filter-name>
       <url-pattern>/*</url-pattern>
       <dispatcher>FORWARD</dispatcher>
       <dispatcher>REQUEST</dispatcher>
   </filter-mapping>

<listener>
       <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
   </listener>
   <listener>
   <listener-class>com.chinalife.common.web.filter.SpringInit</listener-class>
   </listener>
   <listener>
       <listener-class>com.chinalife.contract.userPermissionQuery.utils.NFDFlightDataTaskListener</listener-class>
   </listener>
   <filter>
       <filter-name>OpenSessionInView</filter-name>
       <filter-class>org.springframework.orm.hibernate3.support.OpenSessionInViewFilter</filter-class>
       <init-param>
           <param-name>singleSession</param-name>
           <param-value>true</param-value>
       </init-param>
       <init-param>
           <param-name>flushMode</param-name>
           <param-value>AUTO</param-value>
       </init-param>
   </filter>
   <filter-mapping>
       <filter-name>OpenSessionInView</filter-name>
       <url-pattern>/*</url-pattern>
   </filter-mapping><!--

   <filter>
       <filter-name>urlFilter</filter-name>
       <filter-class>com.chinalife.common.web.filter.UrlFilter</filter-class>
   </filter>
   <filter-mapping>
       <filter-name>urlFilter</filter-name>
       <url-pattern>/*</url-pattern>
   </filter-mapping>

   --><servlet>
       <servlet-name>XFireServlet</servlet-name>
       <servlet-class>
           org.codehaus.xfire.spring.XFireSpringServlet
       </servlet-class>
       <init-param>
           <param-name>config</param-name>
           <param-value>services.xml</param-value>
       </init-param>
   </servlet>
   <servlet-mapping>
       <servlet-name>XFireServlet</servlet-name>
       <url-pattern>/service/*</url-pattern>
   </servlet-mapping>

   <jsp-config>
       <taglib>
           <taglib-uri>/WEB-INF/ecside.tld</taglib-uri>
           <taglib-location>/WEB-INF/ecside.tld</taglib-location>
       </taglib>
       <taglib>
           <taglib-uri>/user-defined-tags</taglib-uri>
           <taglib-location>/common/tlds/user-defined-tags.tld</taglib-location>
       </taglib>
   </jsp-config>

   <welcome-file-list>
       <welcome-file>login.jsp</welcome-file>
   </welcome-file-list>

<mime-mapping>
   <extension>xls</extension>
   <mime-type>application/msexcel</mime-type>
</mime-mapping>
<mime-mapping>
   <extension>txt</extension>
   <mime-type>applcation/txt</mime-type>
</mime-mapping>
</web-app>